Sapphire cover for electronic devices

ABSTRACT

A cover for an electronic device and methods of forming a cover is disclosed. The electronic device may include a housing, and a cover coupled to the housing. The cover may have an inner surface having at least one of an intermediate polish and a final polish, a groove formed on the inner surface, and an outer surface positioned opposite the inner surface. The outer surface may have at least one of the intermediate polish and the final polish. The cover may also have a rounded perimeter portion formed between the inner surface and the outer surface. The rounded perimeter portion may be positioned adjacent the groove. The method for forming the cover may include performing a first polishing process on the sapphire component using a polishing tool, and performing a second polishing process on the groove of the sapphire component forming the cover using blasting media.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional patent application of and claimsthe benefit of U.S. Provisional Patent Application No. 62/129,707, filedMar. 6, 2015, and titled “Sapphire Cover for Electronic Devices,” andU.S. Provisional Patent Application No. 62/042,533, filed Aug. 27, 2014and titled “Sapphire Cover for Electronic Devices,” the disclosures ofwhich are hereby incorporated herein by reference in their entirety.

FIELD

The disclosure relates generally to electronic devices, and moreparticularly to a cover for an electronic device and methods of formingthe cover for the electronic device.

BACKGROUND

Electronic devices continue to become more prevalent in day-to-dayactivities. For example, smart phones, tablet computers and electronicdevices continue to grow in popularity, and provide everyday personaland business functions to its users. These electronic devices mayinclude screens or displays utilized by the user to interact (e.g.,through input/output operations) with the electronic devices and/orreceive information therefrom.

Conventionally, these screens or displays are made from reinforced ormodified glass. However, these glass screens may still be susceptible todamage. Specifically, these conventional screens may scratch, chip orcrack when an undesirable impact event or force (e.g., drop, crushed)occurs with the electronic device. Damage to the screens of theelectronic device may render the device partially or completelyinoperable and/or may prevent the user from utilizing the electronicdevice for its intended purposes.

The use of the crystalline form of alumina (Al₂O₃) (e.g., corundum),commonly known as sapphire, is becoming a viable option for replacingthe glass screen or display. Specifically, with improved manufacturingprocesses of single crystal sapphire, and the improved functionalcharacteristics (such as hardness and strength) of sapphire over glass,sapphire may be an acceptable replacement material for conventionalglass screens and displays. However, the same chemical/elementalcharacteristics that make sapphire an often-superior material choiceover glass may also make the manufacturing of sapphire difficult. Thatis, due to sapphire's hardness, processing or shaping sapphire may bedifficult. For example, where the sapphire display includes curved ornon-planar surfaces, conventional polishing techniques and processes mayfall short of providing an adequate or desired polish on the curved ornon-planar surfaces of the sapphire.

Thus, an improved process for forming and/or polishing a sapphirecomponent including curved or non-planar surfaces may be useful.

SUMMARY

A method of forming a cover for an electronic device. The methodcomprises performing a first polishing process using a polishing tool ona planar surface of the sapphire component and/or a groove formed in thesapphire component adjacent the planar portion. The method alsocomprises performing a second polishing process on the groove of thesapphire component using blasting media.

A method of forming a cover for an electronic device. The methodcomprises forming a groove on an inner surface of a sapphire component,performing at least two intermediate polishing processes on the grooveof the sapphire component, annealing the sapphire component, andperforming a final polishing process on at least a portion of theannealed sapphire component.

An electronic device comprising a housing, and a cover coupled to thehousing. The cover may comprise an inner surface having at least one ofan intermediate polish, or a final polish, a groove formed on the innersurface, and an outer surface positioned opposite the inner surface. Theouter surface may comprise at least one of the intermediate polish, orthe final polish. The cover may also comprise a rounded perimeterportion formed between the inner surface and the outer surface. Therounded perimeter portion may be positioned adjacent the groove.

A method for applying a decorative ink to a cover for an electronicdevice. The method comprises pad printing ink on at least a portion of aplanar surface of the cover. The portion of the planar surface may bepositioned adjacent a groove formed in the cover. The method may alsocomprise positioning a masking structure on the cover adjacent thegroove. The masking comprising a protective film placed on the planarsurface, a spacer coupled to a portion of the protective film, and arigid top component coupled to the spacer. The rigid top component maybe positioned over the ink pad printed on at least the portion of theplanar surface of the cover. Additionally, the method may comprisedirectly applying ink to the groove formed in the cover, and diffusivelyapplying ink to at least a portion of the ink pad printed on at leastthe portion of the planar surface of the cover.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like structural elements, and in which:

FIG. 1 depicts an illustrative perspective view of a wearable electronicdevice according to embodiments.

FIG. 2 depicts an enlarged cross-section view of a portion of theelectronic device of FIG. 1 taken along line 2-2, according toembodiments.

FIGS. 3 and 4 depict enlarged cross-section views of a portion of theelectronic device of FIG. 1 taken along line 2-2, according toadditional embodiments.

FIG. 5 depicts a flow chart of an example process for forming a coverfor an electronic device, according to embodiments.

FIG. 6A depicts a cross-sectional view of sapphire material for forminga cover of an electronic device as depicted in FIGS. 1 and 2, accordingto embodiments.

FIGS. 6B and 6C depict cross-sectional views of the sapphire material ofFIG. 6A undergoing lapping, laser cutting and machining processes forforming the cover for an electronic device as depicted in FIGS. 1 and 2,according to embodiments.

FIG. 6D depicts a cross-sectional view of the sapphire material of FIG.6A undergoing intermediate polishing processes for forming the cover foran electronic device as depicted in FIGS. 1 and 2, according toembodiments.

FIG. 6E depicts a cross-sectional view of the sapphire material of FIG.6A subsequent to performing the intermediate polishing processes asdepicted in FIG. 6D, according to embodiments.

FIG. 6F depicts a cross-sectional view of the sapphire material of FIG.6A subsequent to performing a final polishing process for forming thecover for an electronic device as depicted in FIGS. 1 and 2, accordingto embodiments.

FIG. 6G depicts a cross-sectional view of the sapphire material of FIG.6A undergoing a preliminary pad printing process for forming the coverfor an electronic device as depicted in FIGS. 1 and 2, according toembodiments.

FIG. 6H depicts a cross-sectional view of the sapphire material of FIG.6A undergoing a decorative ink application process for forming the coverfor an electronic device as depicted in FIGS. 1 and 2, according toembodiments.

FIGS. 6I and 6J depict cross-sectional views of the sapphire material ofFIG. 6A undergoing a subsequent pad printing process for forming thecover for an electronic device as depicted in FIGS. 1 and 2, accordingto embodiments.

FIGS. 7A-7E depict a cross-sectional view of sapphire material forforming a cover of an electronic device as depicted in FIGS. 1 and 2,undergoing a decorative ink application process, according toembodiments.

FIGS. 8A-8D depict a cross-sectional view of sapphire material forforming a cover of an electronic device as depicted in FIGS. 1 and 2,undergoing a decorative ink application process, according to furtherembodiments.

FIGS. 9A-9D depict a cross-sectional view of sapphire material forforming a cover of an electronic device as depicted in FIGS. 1 and 2,undergoing a decorative ink application process, according to additionalembodiments.

FIG. 10 depicts a flow chart of an example process for applying adecorative ink to a cover for an electronic device, according toembodiments.

DETAILED DESCRIPTION

Reference will now be made in detail to representative embodimentsillustrated in the accompanying drawings. It should be understood thatthe following descriptions are not intended to limit the embodiments toone preferred embodiment. To the contrary, it is intended to coveralternatives, modifications, and equivalents as can be included withinthe spirit and scope of the described embodiments as defined by theappended claims.

The following disclosure relates to electronic devices, and moreparticularly to a cover for an electronic device and methods of formingthe cover for the electronic device.

In particular embodiments, processes for forming a cover glass, ahousing, or other external feature of an electronic device includeperforming multiple and distinct polishing processes on some or all ofthe surfaces of the sapphire material forming the cover. For example,planar portions of the cover may be polished using a variety ofpolishing processes, such as chemical mechanical polishing (CMP),diamond mechanical polishing (DMP), polishing using polishing padsand/or polishing using blasting media. The polishing processes describedherein may reduce surface roughness, smooth a surface, and/or make asurface more reflective or visually uniform. Curved surfaces, such as arounded perimeter portion or a groove formed within the sapphirematerial, may be polished using a two-part polishing process. Thetwo-part polishing process may include polishing using polishing padsand polishing using blasting media. The blasting media may be a diamondencrusted resin-based material that may have elastic properties to avoiddamaging the surface of the sapphire material during polishing.Additionally, at least a portion of the surfaces of the cover may bepolished after an annealing process is performed on the sapphirematerial. By performing multiple polishing processes, and specificallyutilizing a multi-part polishing process for the curved (or otherwisenon-planar) surfaces of the sapphire material, the cover may be polishedto a desired finish and/or may have desired visual properties when usedwithin an electronic device.

In certain embodiments, additional operations may be performed on thesapphire material after it is shaped and polished. For example, an inkcan be pad printed on a planar surface of the sapphire material adjacentthe curved surface formed in the sapphire material. The planar portionsthat were previously pad printed are then masked using a maskingstructure, and the curved portion is exposed. Further ink is thanapplied to the curved portion, for example by spraying the ink onto thecurved portion. This additional ink may be the same type of ink aspreviously applied, or it may be different.

These and other embodiments are discussed below with reference to FIGS.1-10. However, those skilled in the art will readily appreciate that thedetailed description given herein with respect to these Figures is forexplanatory purposes only and should not be construed as limiting.

FIG. 1 shows an illustrative perspective view of a portable or wearableelectronic device 100 (hereafter, “electronic device”), according toembodiments. Electronic device 100, as shown in FIG. 1, may beimplemented as a smart watch, although this is but one example of asuitable electronic device 100. Electronic device 100 includes, amongstother components discussed herein, a cover 112 having a groove 128formed therein. As discussed herein, cover 112 protects a display 104and/or other internal components positioned within a housing 102 ofelectronic device 100. Additionally as discussed herein, groove 128 mayreceive and/or house a communicative component of electronic device 100,such as an antenna, to reduce the number of components positioned and/orrequiring space within housing 102.

For aesthetic, visual and/or protective purposes, groove 128 formed incover 112 may be polished, inked and/or painted. The polishing, inkingand/or painting of groove 128 may provide uniform surface polishes ofcover 112, to provide a uniform color or appearance to a user ofelectronic device 100 and/or to prevent the antenna positioned withingroove 128 from being visible. The geometry of groove 128, andspecifically the curved surface forming groove 128, may require uniqueprocesses for polishing, inking and/or painting the curved surface, whencompared to the planar portions of cover 112, as discussed herein. Inone embodiment, groove 128 undergoes a two-part polishing processincluding performing an initial polishing step using a polishing tool,such as a brush, and subsequently providing a blast media to groove 128to perform a subsequent polishing step. From there, and after polishinggroove 128, ink may be applied to groove 128 using a spray and/or padprinting process. This process ensures groove 128 has the uniquegeometry and/or the curved surface is polished and/or inked to a similarfinish as the planar portions of cover 112.

In another embodiment, an interior of cover 112 including groove 128 canbe inked and/or painted using a two-step process. Initially, certaininterior planar portions of cover 112 can be painted, and subsequentlymasked, leaving groove 128 exposed. Once masked, ink may be sprayedand/or directly applied to groove 128, such that the masks prevent inkfrom being sprayed onto the previously painted planar portions of cover112. The ink sprayed on groove 128 may be applied such that the inkformed on groove 128 is even with the ink applied to the planar portionsof cover 112 (e.g., the resulting ink layer has a thickness that issubstantially uniform and lacking in transitions), and/or so there is aseamless transition between the ink applied to the curved portion ofcover 112 forming groove 128 and the planar portions of cover 112.Accordingly, the resulting ink layer covering both groove 128 and planarportions of cover 112 appears continuous and without any transitionvisible to the human eye.

FIG. 2 depicts an enlarged cross-section view of a portion of electronicdevice 100 of FIG. 1 taken along line 2-2, according to an embodiment.With respect to this particular embodiment, FIG. 2 shows a cross-sectionview of a portion of housing 102 and cover 112 of electronic device 100.A space or opening 118 may be formed between housing 102 and cover 112;the opening 118 may receive additional components of electronic device100. More specifically, opening 118 of electronic device 100 may receiveand/or may provide space for certain or all internal components ofelectronic device 100. In the non-limiting example of FIG. 2, display104 is shown in phantom and may be positioned within at least a portionof opening 118 formed between cover 112 and housing 102. As discussedherein with respect to FIG. 1, display 104 may be formed from anysuitable user-interactive display technology, and may have touch-sensingfunctionality or may be associated with a touch sensor. Additionally,display 104 may be protected by cover 112 positioned above and/orcoupled to display 104 positioned within a portion of opening 118 ofelectronic device 100. The cover 112 may be transparent or translucent,fully or partially, in certain embodiments.

Cover 112 of electronic device 100 may be formed from a substantiallyannealed and polished sapphire material. That is, and as discussedherein, cover 112 may be formed from an annealed sapphire materialhaving all or some portions of the surface polished prior to and/orsubsequent to the annealing. By annealing the sapphire material, cover112 may be provided with increased hardness, and/or may also have planarsurfaces that may be more easily processed and/or may facilitatetransparency in the sapphire material forming cover 112. Additionally,the process of annealing the sapphire material may also fill in or sealcracks or other surface defects formed in the sapphire material duringprocessing.

As shown in FIG. 2, cover 112 may be coupled to housing 102. Morespecifically, a portion of cover 112 may be positioned above and, may becoupled to, a shelf portion 120 formed adjacent a perimeter of housing102. Shelf portion 120 may be formed substantially around the entireperimeter of housing 102, and may receive and/or couple a portion ofcover 112 to housing 102. As shown in FIG. 2, cover 112 may be coupledto shelf portion 120 of housing 102 using an adhesive, such as adhesivetape. However, it is understood that cover 112 may be coupled to shelfportion 120 of housing 102 using any suitable coupling component ortechnique. In additional non-limiting examples, cover 112 of electronicdevice 100 may be coupled to housing 102 using chemicals, adhesives,bonding agents, laser welding, melting, and mechanical couplingcomponents (snap-fit structures, detents, screws, and the like).

Cover 112, as shown in FIG. 2, may define an inner surface 124, and anouter surface 126 positioned opposite inner surface 124. Inner surface124 may be positioned adjacent to opening 118 and may not be exposed toa user of electronic device 100. As shown in FIG. 2, and as discussedherein, display 104 (shown in phantom) may be positioned adjacent toand/or may be coupled to inner surface 124. Outer surface 126 may beexposed to, and/or may be contacted by a user of electronic device 100when the user is interacting with display 104.

As shown in FIG. 2, cover 112 may have a groove 128 formed on innersurface 124. More specifically, groove 128 may be formed on innersurface 124, substantially around the entire perimeter of cover 112.Groove 128 may be formed partially through a portion of cover 112.

As a result of forming groove 128 on inner surface 124 of cover 112, thethickness of cover 112 may vary. That is, as shown in FIG. 2, a firstthickness (T1) of cover 112 may be defined between inner surface 124 ofgroove 128 and outer surface 126. This first thickness (T1) may besubstantially smaller than a second thickness (T2) of a portion of cover112 defined in a non-groove bearing region, such as above the display104. As discussed herein, the first thickness (T1) may alter and/oraffect various polishing processes performed on the sapphire materialforming cover 112. Additionally as discussed herein, groove 128 may beformed in cover 112 using a plurality of processes includinglaser-cutting groove 128 on inner surface 124, and subsequently computernumerical control (CNC) machining the laser cut groove 128 formed incover 112.

Groove 128 may be formed in cover 112 for a variety of functions. In anon-limiting example, groove 128 may be formed in cover 112 to provideadditional space within electronic device 100 for additional components.In the non-limiting example, groove 128 may receive and/or may house anantenna (not shown) of electronic device 100, such that the antenna maybe positioned within groove 128 of cover 112 without occupying spacewithin opening 118 of electronic device 100. The antenna may be used toshare (e.g., send, receive) data collected and/or determined by theelectronic device 100. In another non-limiting example, groove 128 mayprovide a coupling surface for display 104, where a portion of display104 may be positioned within and/or coupled to groove 128 to positiondisplay 104 adjacent inner surface 124 of cover 112.

In a further, non-limiting example, groove 128 may be formed withincover 112 to provide a visual boundary or border for display 104. Morespecifically, and as shown in FIG. 2, a decorative ink 150 may beapplied to inner surface 124 of groove 128 positioned substantiallyaround the entire perimeter of cover 112, such that the decorative ink150 may provide an ink border around display 104 of electronic device100. As a result of forming groove 128 between display 104 and housing102, decorative ink 150 may be applied to inner surface 124 of groove128 to provide a decorative border around display 104, so a user ofelectronic device 100 may clearly identify the interactive area ofdisplay 104. Decorative ink 150 may be visible through outer surface 126as a result of the transparent properties of the sapphire materialforming cover 112. As discussed herein, decorative ink 150 may beapplied to inner surface 124 of groove 128 using a plurality of padprinting processes and by spraying decorative ink within groove 128.

Cover 112 may also include distinct portions. More specifically, asshown in FIG. 2, cover 112 may have a substantially planar or linearportion 132 and rounded perimeter portion 134. Substantially planarportion 132 may be formed in the center of cover 112 (or as a center ofthe cover) such that display 104 may be completely visible and/or notdistorted by cover 112. That is, substantially planar portion 132 may beformed adjacent to the perimeter of cover 112. Display 104 may be formedin substantial alignment with planar portion 132 of cover 112 to allowdisplay 104 to be completely viewed by a user of electronic device 100,without potentially altering the image of display 104 due to a curvaturein cover 112 (e.g., rounded perimeter portion 134).

Rounded perimeter portion 134 may be formed around at least a portion ofthe perimeter of cover 112. More specifically, and as shown in FIG. 2,rounded perimeter portion 134 may form the perimeter of cover 112, andmay be positioned adjacent to the perimeter of housing 102. Roundedperimeter portion 134 may be positioned adjacent to groove 128 formed oninner surface 124. As shown in FIG. 2, rounded perimeter portion 134 maybe coupled to shelf portion 120, and ultimately couple cover 112 tohousing 102. As discussed herein, planar portion 132 and roundedperimeter portion 134 of cover 112 may be formed in a shaping process ofthe sapphire material used to form cover 112. That is, and as discussedherein, the sapphire material may be lapped, machined and/or laser cutto from planar portion 132 and rounded perimeter portion 134 of cover112.

Substantially all surfaces (e.g., inner surface 124, outer surface 126)of cover 112 may be polished. More specifically, as shown in FIG. 2,both inner surface 124 and outer surface 126 of cover 112 may have anintermediate polish 136 and/or a final polish 138. As discussed herein,intermediate polish 136 may be formed on a surface of cover 112 prior toperforming an annealing process on the sapphire material forming cover112. Additionally as discussed herein, final polish 138 may be formed ona surface of cover 112 subsequent to performing the annealing process onthe sapphire material forming cover 112.

In a non-limiting example, as shown in FIG. 2, outer surface 126 ofcover 112 may only have final polish 138. That is, final polish 138 maysubstantially cover all of outer surface 126 of cover 112, includingboth planar portion 132 and rounded perimeter portion 134. Distinct fromouter surface 126, inner surface 124 of cover 112 may have bothintermediate polish 136 and final polish 138. More specifically, asshown in FIG. 2, inner surface 124 of planar portion 132 may have finalpolish 138, and inner surface 124 of rounded perimeter portion 134 ofcover 112 may have intermediate polish 136. Additionally as shown inFIG. 2, intermediate polish 136 may also be formed on inner surface 124including groove 128 of cover 112.

The respective polishes (e.g., intermediate polish 136, final polish138) may be formed on distinct portions of cover 112 based on, at leastin part, the material used to form cover 112, the processes used to formcover 112, and/or the dimensions of cover 112. For example, dependent onthe dimension of first thickness (T1), and/or the difference betweenfirst thickness (T1) and second thickness (T2) of cover 112, a portionor all of the surfaces (e.g., inner surface 124, outer surface 126) ofrounded perimeter portion 134 may or may not be polished during a finalpolishing process, as discussed herein.

As one example, certain surfaces may not be polished to avoid and/orprevent damage (e.g., breakage, cracking) to cover 112 during the finalpolishing process. That is, where first thickness (T1) is below apredetermined threshold thickness inner surface 124 and/or outer surface126 forming a part of rounded perimeter portion 134 of cover 112 may notbe subject to a final polish 138. The predetermined threshold thicknessfor cover 112 may be a minimal thickness of rounded perimeter portion134, including groove 128, that may withstand the final polishingprocess to provide final polish 138 without damaging cover 112.

In a non-limiting example, as shown in FIG. 2 and discussed herein,cover 112 may be formed from an annealed sapphire material. Additionallyas discussed herein, the first thickness (T1) in cover 112 betweengroove 128 and outer surface 126 may be substantially smaller than thesecond thickness (T2) in cover 112. First thickness (T1) may also besubstantially equal to, or slightly above, a predetermined thresholdthickness for cover 112. As a result of the dimension of first thickness(T1) of cover 112, inner surface 124 forming part of rounded perimeterportion 134 of cover 112 may be subject to intermediate polish 136, andnot final polish 138, to substantially prevent any damage to cover 112.However, because first thickness (T1) may be substantially equal to, orslightly above, a predetermined threshold thickness, a final polish maybe performed or placed on outer surface 126 of rounded perimeter portion134 without substantially damaging cover 112.

In another non-limiting example, as shown in FIG. 3, all surfaces (e.g.,inner surface 124, outer surface 126) of cover 112 may include finalpolish 138. That is, both inner surface 124 and outer surface 126 ofplanar portion 132 and rounded perimeter portion 134 of cover 112 mayonly have final polish 138. In the non-limiting example shown in FIG. 3,all surfaces of cover 112 may have final polish 138 as a result of firstthickness (T1) of cover 112 being substantially above or greater thanthe predetermined threshold thickness, as discussed herein. As such,both inner surface 124 and outer surface 126 of cover 112 may undergo afinal polishing process, as discussed herein, without potentiallydamaging cover 112.

In an additional non-limiting example, as shown in FIG. 4, inner surface124 and outer surface 126 of rounded perimeter portion 134 of cover 112may include intermediate polish 136. That is, both inner surface 124 andouter surface 126 of rounded perimeter portion 134 of cover 112 may onlyhave intermediate polish 136, and inner surface 124 and outer surface126 of planar portion 132 may have final polish 138. In the non-limitingexample shown in FIG. 4, all surfaces of rounded perimeter portion 134may include intermediate polish 136 as a result of first thickness (T1)of cover 112 being substantially below or smaller than the predeterminedthreshold thickness, as discussed herein. As such, both inner surface124 and outer surface 126 of rounded perimeter portion 134 of cover 112may not undergo a final polishing process, as discussed herein, toprevent and/or avoid damaging cover 112.

FIG. 5 depicts an example process for forming a cover for an electronicdevice. Specifically, FIG. 5 is a flowchart depicting one exampleprocess 500 for forming a cover for an electronic device. In some cases,the process 500 may be used to form one or more covers 112 forelectronic device 100, as discussed above with respect to FIGS. 1-4.

In operation 502, a sapphire component may be shaped. In a non-limitingexample, a piece of sapphire material may undergo various shapingprocesses, to provide a beginning shape of a cover for an electronicdevice. The shaping of the sapphire component may be achieved by lappingthe sapphire material to thin the component. Lapping of the sapphirematerial may also form planar portions of the sapphire component. Theshaping may also be performed by forming a rounded perimeter portion onan outer surface and/or about the perimeter of the sapphire material.

As one non-limiting example, rounded perimeter portions may be formed onthe sapphire material, adjacent to the planar portions, using a computernumerical control (CNC) machining process. As another example, therounded perimeter portions may be formed by laser ablating material fromthe sapphire surface. The shaping process of the sapphire component mayfurther include laser cutting a rough groove into an inner surface ofthe sapphire material, and subsequently machining the laser cut grooveformed in the sapphire material. The machining of the laser cut groovemay be accomplished using any suitable material removal processincluding, but not limited to, CNC machining, drilling, milling, andgrinding. Additionally, the rounded perimeter portions and groove formedwithin the sapphire material may be positioned adjacent one another.That is, the groove may be positioned adjacent to and/or substantiallywithin the rounded perimeter portions formed in the sapphire material.

In operation 504, intermediate polishing processes may be performed onthe sapphire component. At least two distinct polishing processes may beperformed on portions of the sapphire component, although both need notbe performed in a single embodiment. More specifically and by way ofexample, a first polishing process may be performed on the sapphirecomponent using a polishing brush or other polishing tool, and a secondpolishing process may be performed on the sapphire component usingblasting media.

In some embodiments, the first polishing process and the secondpolishing process may be performed at least on the surfaces of therounded perimeter portions of the sapphire component, and the groove ofthe sapphire component. That is, inner and outer surfaces of the roundedperimeter portions, and the groove formed on the sapphire component, mayundergo a polishing process using a polishing tool and blasting media.The polishing tool, such as a brush, used in the first polishing processmay be any suitable, compliant polishing tool, one example of which is apig hair brush or pad. The blasting media utilized in the secondpolishing process may be a diamond encrusted resin-based material, whichis a material formed from resin and diamond pieces, fragments, particlesand the like. The diamond particles may be encased or otherwise fully orpartially contained within the resin. Other materials, such as sapphire,may be used in place of diamond in some embodiments.

The diamond encrusted resin-based material may be applied to thesurfaces of the rounded perimeter portions of the sapphire componentusing a dispensing system that may dispense, apply, or otherwise providethe blasting media to the surfaces of the sapphire component with highforce or pressure to polish the surface. For example, the diamondencrusted resin-based material may be blown or otherwise propelledtoward the surface to be polished. In order to prevent damage to thesurface of the sapphire component, the diamond encrusted resin-basedmaterial may have substantially elastic properties, and maysubstantially deform when first contacting the surface of the sapphirecomponent. The rounded perimeter portions and the groove formed in thesapphire component may undergo the first polishing process (e.g.,polishing tool) and second polishing process (e.g., blasting media) toensure the non-linear and/or non-planar surfaces of the roundedperimeter portions and the groove are adequately polished.

Intermediate polishing processes may be performed in operation 504.Specifically, other portions of the sapphire component may undergodistinct polishing processes when performing the intermediate polishingprocesses on the sapphire component. The planar portions of the sapphirecomponent may be polished using a chemical mechanical polishing (CMP)process and/or a diamond mechanical polishing (DMP) process. Theseintermediate polishing processes may be performed on the remainingportions of the sapphire component to ensure that all surface of thesapphire component may have an intermediate polish.

In operation 506, the sapphire component may be annealed. In anon-limiting example, the polished sapphire component may undergo anannealing process to strength the sapphire material used to form thecover for the electronic device. The annealing process may substantiallyfill or seal any cracks or damage of the sapphire component formedduring the shaping processes of operation 502 and/or the polishingprocesses in operation 504.

In operation 508, a final polishing process may be performed on thesapphire component. In a non-limiting example, a final polishing processmay be performed on the surface of at least a portion of the annealedsapphire component. The final polishing process may further includepolishing the inner surface of the annealed sapphire component adjacentto, but not within, the groove, or polishing the inner surface of theannealed sapphire component including the groove. The groove may befinally polished using a compliant polishing pad, where at least aportion of the pad may contour into the groove, and polish the portionof the inner surface formed within the groove. In addition, the finalpolishing process may include polishing the outer surface of theannealed sapphire component adjacent to, but not on, the roundedperimeter portions, or polishing the outer surface of the annealedsapphire component including the rounded perimeter portions. Like thegroove, the rounded perimeter portions may be polished using a compliantpolishing pad that may contour around the rounded outer surface of therounded perimeter portions of the sapphire component.

The portions of the surface that may undergo the final polishing processmay be dependent, at least in part, on the dimension of the roundedperimeter portions formed in the sapphire component, and specifically,the thickness between the inner surface of the groove and the outersurface of the sapphire component. Where the thickness is smaller than apredetermined thickness threshold for the sapphire component, the finalpolishing of the rounded perimeter portions in operation 508 may damagethe sapphire component forming the cover for the electronic device.

In optional operation 510, a decorative ink may be applied to thesapphire component. In a non-limiting example, a decorative ink may beapplied to the groove formed on the inner surface of the sapphirecomponent, and/or portions of the cover positioned adjacent the groove.Applying the decorative ink to the groove and/or portions of the coveradjacent the groove may include performing a preliminary pad printingprocess in the groove. The preliminary pad printing process may providean initial layer of ink and/or a decorative image to the surface of thegroove.

Applying the decorative ink may also include covering a portion of thesapphire component positioned adjacent the groove with a protectivemask, and subsequently spraying the groove with the decorative ink. Theprotective mask, covering the portions of the sapphire componentadjacent the groove, may prevent any sprayed decorative ink fromundesirably contacting or forming on the sapphire component outside ofthe groove. Finally, the applying of the decorative ink may includeperforming a subsequent pad printing process in the groove including thedecorative ink. The subsequent pad printing process may provide thegroove of the sapphire component with the final image, design and/orpaint to be viewed by a user of the electronic device including thecover formed from the sapphire component.

The final polishing of at least a portion of the sapphire component inoperation 508 may form the cover to be utilized and/or implementedwithin an electronic device. The optional operation 510 may be performedon the sapphire component to provide a cosmetic feature of the cover, asdiscussed herein.

It is understood that the processes discussed herein for formingpolished cover 112 for electronic device 100 may be performed on othercomponents having distinct features and/or geometries. That is, theprocesses discussed herein with respect to FIG. 5 may be performed on avariety of components that may have features having non-planar and/orrelatively tight or narrow tolerances that make conventional ortraditional polishing processes difficult. Additionally, the processesdiscussed herein may also be performed on any alumina material, orsubstantially rigid material.

Turning to FIGS. 6A-6J, cover 112 is shown undergoing various operationsthat may be performed in accordance with process 500 of FIG. 5. It isunderstood that similarly numbered components may function in asubstantially similar fashion. Redundant explanation of these componentshas been omitted for clarity.

FIG. 6A depicts an enlarged, front cross-section view of a portion ofsapphire material 140 that may be form cover 112 (see, FIG. 6F). Asdiscussed herein, sapphire material 140 may undergo various shapingprocesses to form cover 112. Sapphire material 140, as shown in FIG. 6Amay be cut from a large boule of sapphire material grown specifically toform cover 112. Sapphire material 140 may be cut from a larger boule ofmaterial to a workable size that may undergo various processes to form asingle cover 112 for electronic device 100. As shown in FIG. 6A,sapphire material 140 may be cut from the boule of material using anysuitable cutting process including laser cutting and diamond cutting.

Additionally, surfaces of sapphire material 140 may undergo a lappingprocess. In a non-limiting example, as shown in FIG. 6A, at least outersurface 126, and in certain embodiments all surfaces, of sapphirematerial 140 may undergo a rough lapping process. The rough lappingprocess may remove any excess material formed on the surfaces ofsapphire material 140 in order to make the surfaces of sapphire material140 substantially flat and/or planar. The rough lapping process, andultimately the planarization of the surfaces of sapphire material 140may allow for easier subsequent processing on sapphire material 140.

FIG. 6B depicts sapphire material 140 that has undergone one or moremachining processes to form a profile for cover 112. For example,sapphire material 140 may undergo a machining process to form roundedperimeter portion 134. The machining process may include a CNC machiningprocess to remove material from sapphire material 140 to form roundedperimeter portion 134.

Additionally, as shown in FIG. 6B, groove 128 may be preliminarilyformed in sapphire material 140 using a laser etching process. As shownin FIG. 6B, and with comparison to FIG. 6C, groove 128 formed insapphire material 140 using the laser etching process may be apreliminary shape that may be subsequently processed and/or reshaped.

Turning to FIG. 6C, sapphire material may be subsequently machined toform a final groove 128 on inner surface 124. More specifically, roughgroove 128, shown in FIG. 6B may undergo additional CNC machiningprocesses (e.g., rough CNC, fine CNC, and the like) to form asubstantially final shape for groove 128 in sapphire material 140.

Additionally as shown in FIG. 6C, cavity 141 of sapphire material 140may be formed using a machining process. In a non-limiting example, aCNC machining process may be performed opposite outer surface 126 toremove material from sapphire 140. The CNC machining process may formcavity 141 adjacent inner surface 124 of sapphire material 140.Additionally, cavity 141 may be formed adjacent and/or between groove128 formed in sapphire material 140. As discussed herein, cavity 141 mayprovide space within opening 118 of electronic device 100 to housecomponents of electronic device 100.

As shown in FIG. 6C and as discussed herein, the shaping of sapphirematerial 140, and more specifically, the lapping, laser ablating andmachining of sapphire material 140 to form groove 128, may substantiallyreduce the thickness of cover 112 in rounded perimeter portion 134. Asshown in FIG. 6C, the first thickness (T1) between groove 128 and outersurface 126 may be substantially smaller than the second thickness (T2)formed between inner surface 124 and outer surface 126 in planar portion132 of cover 112. Additionally, in the non-limiting example as shown inFIG. 6C, the first thickness (T1) may be substantially equal to, orslightly greater than, a predetermined threshold thickness for cover112. As discussed herein, the first thickness (T1), when compared to thepredetermined threshold thickness may affect further processing (e.g.,final polishing process) of cover 112. The shaping of sapphire material140 to form the cover 112, as shown in FIGS. 6A-C, may correspond tooperation 502 of FIG. 5.

FIG. 6D shows sapphire material 140 undergoing intermediate polishingprocesses. In a non-limiting example, as shown in FIG. 6D, sapphirematerial 140 forming cover 112 (see, FIG. 6F) may have undergone some ofthe intermediate polishing processes. As shown in FIG. 6D, a portion ofinner surface 124 may have undergone polishing processes to formintermediate polish 136 on a portion of inner surface 124. Morespecifically, planar portion 132 of inner surface 122 may be polishedusing a chemical mechanical polishing (CMP) and/or a diamond mechanicalpolishing (DMP) process.

FIG. 6D also shows sapphire material 140 currently undergoing a secondpolishing process using blasting media 142. In a non-limiting example,inner surface 124 of rounded perimeter portion 134 is shown undergoing apolishing process that utilizes blasting media 142. The blasting media142 may be a diamond encrusted resin-based material or a diamondimpregnated elastomer resin, that may contact inner surface 124 ofsapphire material 140 under high-pressure to substantially polish innersurface 124. The diamond-encrusted resin-based material may also haveelastic properties, such that when the blasting media 142 is provided tothe surface of sapphire material 140 under high-pressure and/orhigh-speeds, blasting media 142 may substantially deform to reduce theimpact force of blasting media 142 on inner surface 124. As shown inFIG. 6D, blasting media 142 may be provided to inner surface 124 ofrounded perimeter portion 134, and specifically groove 128, viadispensing nozzle 144. Blasting media 142 may be dispensed via nozzle144 and may subsequently slide or flow along inner surface 124 of groove128 to form intermediate polish 136 on inner surface 124. Subsequent to,or prior to, polishing inner surface 124 of rounded perimeter portion134 using blast media 142, inner surface 124 may undergo anotherpolishing process using a polishing brush (not shown). The polishingbrush or pad used to polish inner surface 124 of groove 128 may be anysuitable polishing brush or pad that may be compliant and/or deformablesuch that the polishing brush or pad may polish the non-planar or curvedsurface of rounded perimeter portion 134 and/or groove 128. By usingblasting media 142 and the compliant polishing brush or pad (not shown)to polish inner surface 124 of rounded perimeter portion 134 and/orgroove 128, it may be ensured that inner surface 124 of roundedperimeter portion 134, including groove 128, may be adequately polished.That is, because of the compliant and/or deformable properties ofblasting media 142 and the compliant polishing brush or pad, thenon-planar surfaces of rounded perimeter portion 134 may be adequatelypolished using the processes discussed herein.

Also shown in FIG. 6D, substantially all of outer surface 126 may haveundergone polishing processes to form an intermediate polish 136 onouter surface 126. In a non-limiting example, and similar to planarportion 132 of inner surface 124, planar portion 132 of outer surface126 may be polished using a CMP process and/or a DMP process.Additionally, outer surface 126 of rounded perimeter portion 134 mayhave undergone two polishing processes to form intermediate polish 136,as similarly discussed and shown in FIG. 6D with respect to innersurface 124 of rounded perimeter portion 134. That is, the two polishingprocesses performed on outer surface 126 of rounded perimeter portion134 may include a first polishing process using a polishing brush or pad(not shown), and a second polishing process using blasting media 142, asdiscussed herein. The intermediate polishing of sapphire material 140forming cover 112, as shown in FIG. 6D, may correspond to operation 504of FIG. 5.

FIG. 6E depicts sapphire material 140 forming cover 112 after completionof the intermediate polishing processes shown in FIG. 6D. All surfacesof sapphire material 140 forming cover 112 may have intermediate polish136. In a non-limiting example, both inner surface 124 and outer surface126 of planar portion 132 and rounded perimeter portion 134 may onlyhave intermediate polish 136.

Additionally, FIG. 6E shows sapphire material 140 after an annealingprocess has been performed. More specifically, sapphire material 140,including all surfaces within intermediate polish 136, may undergo anannealing process to fill or otherwise seal any cracks or damage done tothe sapphire material during the shaping processes or the polishingprocesses. The annealing of sapphire material 140 may also harden thesapphire. The annealing of sapphire material 140 generally correspondsto operation 506 of FIG. 5.

FIG. 6F shows sapphire material 140 subsequent to the final polishingprocesses. In a non-limiting example, as shown in FIG. 6F, sapphirematerial 140 forming cover 112 may have undergone final polishingprocesses to form final polish 138 on at least a portion of the surfacesof cover 112. As shown in FIG. 6F, outer surface 126 of cover 112 mayonly have final polish 138. That is, final polish 138 may substantiallycover all of outer surface 126 of cover 112 included in both planarportion 132 and rounded perimeter portion 134. Distinct from outersurface 126, inner surface 124 of cover 112 may have both intermediatepolish 136 and final polish 138. More specifically, as shown in FIG. 6F,inner surface 124 of cover 112 included in planar portion 132 may havefinal polish 138 and inner surface 124 of rounded perimeter portion 134of cover 112 may have intermediate polish 136. Additionally as shown inFIG. 6F, intermediate polish 136 may also be formed in groove 128 ofcover 112. Intermediate polish 136 formed on inner surface 124 ofrounded perimeter portion 134 may be formed and remain through theannealing process of sapphire material 140. That is, intermediate polish136 may remain on inner surface 124 during the final polish process as aresult of forming intermediate polish 136 on inner surface prior toannealing sapphire material 140 and/or not performing a final polishingprocess on inner surface 124 of rounded perimeter portion 134 afterperforming the annealing process. As discussed herein, the portions ofsurface of cover 112 that may or may not have final polish 138 may bedependent, at least in part, on thickness of cover 112 between groove128 and outer surface 126.

Similar to the intermediate polishing process discussed herein withrespect to FIG. 6D, the final polishing process may include a variety ofpolishing processes. That is, dependent upon the surface (e.g., innersurface 124, outer surface 126) and/or the portion (e.g., planar portion132, rounded perimeter portion 134) of cover 112 being finally polished,the polishing process may vary. For example, as shown in FIG. 6F and assimilarly discussed herein with respect to FIG. 6D, outer surface 126 ofplanar portion 132 may be polished using a CMP and/or a DMP process,while outer surface 126 of rounded perimeter portion 134 may be polishedusing two distinct polishing processes; one process using a polishingbrush or pad, and one process using blast media 142 (see, FIG. 6D). Thefinal polishing process performed cover 112, as shown in FIG. 6F, maycorrespond to operation 508 in FIG. 5.

FIGS. 6G-6J generally depict the process of applying a decorative ink(for example, as shown in FIGS. 6H-6J) into groove 128 formed insapphire material 140. The applying of the decorative ink to groove 128,as shown in FIGS. 6G-6J, may correspond to optional operation 510 inFIG. 5.

Prior to the application of the decorative ink, a preliminary padprinting process may be performed on groove 128 of cover 112. In anon-limiting example, as shown in FIG. 6G, a preliminary printing pad146 may be aligned with groove 128, and may move toward cover 112 tocontact groove 128 during a preliminary pad printing process.Preliminary printing pad 146 may contain a decorative ink and/or adecorative image formed from ink, and may provide the ink/image togroove 128 by contacting inner surface 124 within groove 128. A user orviewer of electronic device 100 may see decorative ink and/or decorativeimage through transparent cover 112. The process may be consideredpreliminary insofar as another ink deposition process (e.g., asubsequent process) may be performed after the pad printing, at least insome embodiments.

The process of applying the decorative ink to groove 128 may alsoinclude covering a portion of sapphire material 140 positioned adjacentgroove 128 with a protective mask 148. That is, and as shown in FIG. 6H,protective mask 148 may be disposed on and substantially cover innersurface 124 of cover 112, except for the portion of inner surface 124included in groove 128. As discussed herein, protective mask 148 maysubstantially protect and/or prevent any sprayed decorative ink 150 fromundesirably contacting or forming on inner surface 124, other than ingroove 128.

FIG. 6H depicts another process for applying decorative ink 150 intogroove 128 of cover 112. In a non-limiting example, FIG. 6H shows theprocess of spraying groove 128 with a decorative ink 150. Decorative ink150 may be sprayed or applied to inner surface 124 of groove 128 usingsprayer 152, to ensure all of inner surface 124 in groove 128 is coveredby decorative ink 150. As discussed herein, decorative ink 150 may forma second ink layer and/or second decorative image within groove 128.

The applying of the decorative ink may finally include performing asubsequent pad printing process on groove 128 including decorative ink150. In a non-limiting example, as shown in FIGS. 6I and 6J, a final orsubsequent pad printing process may be performed on groove 128 using adistinct printing pad 154. As shown in FIG. 6I, prior to performing thefinal or subsequent pad printing process on groove 128, protective mask148 may be removed from inner surface 124 of cover 112. However, it isunderstood that protective mask 148 may also be removed after thesubsequent pad printing process on groove 128 to continue to protectinner surface 124 from undesirable decorative ink 150 application to aportion of inner surface 124.

Similar to preliminary printing pad 146 as discussed herein with respectto FIG. 6G, distinct printing pad 154 may be aligned with groove 128,and may move toward cover 112 to contact groove 128 during a final orsubsequent pad printing process. Distinct printing pad 154 may contain afinal decorative ink layer and/or a final decorative image formed fromink, and may provide the ink/image to groove 128 by contacting innersurface 124 within groove 128. Additionally, distinct printing pad 154may contact groove 128 to remove any excess decorative ink that may besprayed on inner surface 124 of groove 128 during the spraying process,as shown and discussed herein with respect to FIG. 6H. The finaldecorative ink layer and/or final decorative image, as shown in FIG. 6J,may be seen by a user of electronic device 100 (see, FIG. 1) includingcover 112.

It is understood that sapphire material 140 forming cover 112 mayundergo further processes subsequent to the polishing and/or painting ofgroove 128, as discussed herein with respect to FIGS. 6A-6J. That is,subsequent to the polishing of groove 128 and/or subsequent to thepainting of groove 128, cover 112 formed from sapphire material 140 mayundergo further formation processes. Various portions and/or surfaces ofsapphire material 140 forming cover 112 may undergo a plurality ofprocesses including rough/fine CNC machining processes, DMP processes,lapping processes, chemical mechanical polishing (CMP) processes and/orcoating processes. Each process performed on the various portions and/orsurface of sapphire material 140 may aid the formation of cover 112. Innon-limiting examples, performing a fine CNC machining process withincavity 141 and/or on inner surface 124 may improve a surface finish oninner surface 124, or performing a CMP on inner surface 124 withincavity 141 may reduce fogginess within cover 112. In an additionalnon-limiting example, performing a DMP process on sidewalls of groove128 in perimeter portion 134 may maintain edge shape to meet cosmetictolerances for cover 112.

Groove 128 and/or portions of cover 112 surrounding groove 128 may bepainted or inked using distinct processes, such as those discussed abovewith respect to FIGS. 6G-6J. In non-limiting examples shown in FIGS.7A-9D, groove 128 and the portions of cover 112 surrounding groove 128may be painted or inked using two distinct processes, which includes padprinting, and spraying ink into groove 128 and portions of cover 112surrounding groove 128. As discussed herein, the non-limiting examplesmay also utilize a masking structure to prevent ink from being appliedto undesired portions of cover 112.

As shown in FIG. 7A, cover 112 may initially have ink 150 a applied to aportion of inner surface 124 adjacent groove 128. In a non-limitingexample, ink 150 a formed on inner surface 124 may be formed adjacentgroove 128 and may end or stop at a transition point 156 of cover 112.Transition point 156 may be understood as the portion of cover 112 whereinner surface 124 is no longer planar or parallel with outer surface126, but rather, transition point 156 may include the beginning ofgroove 128 formed in cover 112. Additionally, transition point 156 mayalso separate planar portion 132 and rounded perimeter portion 134 ofcover 112. As such, ink 150 a may only be applied on a planar portion ofinner surface 124 of cover 112. Ink 150 a may be formed on inner surface124 adjacent groove 128 using, for example, a pad printing process or asilk screening process.

Although discussed herein as ending at and/or aligned with transitionpoint 156, it is understood that ink 150 a may stop prior to reachingtransition point 156. That is, ink 150 a may not be aligned withtransition point 156, but rather, may end just prior to and/or adjacentto transition point 156 of cover 112.

Once ink 150 a is pad printed on inner surface 124 of cover 112, amasking structure 158 may be placed over inner surface 124. In anon-limiting example shown in FIG. 7B, masking structure 158 may beformed over and/or on a portion of inner surface 124, over at least aportion of the ink 150 a and adjacent to the groove 128. Maskingstructure 158 may be formed from a protective film 160 placed on theinner surface 124 of cover 112, a spacer 162 coupled to the protectivefilm 160, and a rigid top component 164 positioned above spacer 162. Asdiscussed herein, masking structure 158 may allow ink to be sprayed intogroove 128, while simultaneously prevent ink from being sprayed on theentirety of ink 150 a applied to inner surface 124, and/or directly oninner surface 124. Furthermore, and as discussed herein, maskingstructure 158 may also allow for there to be a smooth transition and/ora substantially uniform thickness between ink 150 a that may be appliedusing a pad printing process and ink 150 b (see, FIG. 7C) that may beapplied using a spray process. In many embodiments, any transitionbetween the inks 150 a, 150 b is not detectable to the human eye.

Protective film 160 may be coupled directly to inner surface 124 ofcover 112. Additionally, and as shown in FIG. 7B, a portion ofprotective film 160 may also be coupled to and/or substantially cover aportion of ink 150 a, opposite groove 128 and transition point 156 a.Protective film 160 may cover the portion of ink 150 a positionedopposite groove 128 to ensure that no ink may be sprayed directly ontoinner surface 124 of cover 112 during a spraying process, as discussedherein. Protective film 160 may be coupled to inner surface 124, and aportion of ink 150 a, using any suitable adhesive (not shown) having lowtack properties and/or characteristics. Adhesive having low tackproperties may be used to adhere or couple protective film 160 to innersurface 124 and/or ink 150 a to prevent protective film 160 frombecoming uncoupled from inner surface 124. Additionally, the low tackproperties of the adhesive used on protective film 160 may allowprotective film 160 to be easily removed (i.e., no adhesive residue lefton inner surface 124) and/or prevent protective film 160 from removingink 150 a from inner surface 124 when masking structure 158 is removedfrom cover 112, as discussed herein. In some implementations, theprotective film 160 is placed on the inner surface 124 and a portion ofthe ink 150 a without the use of an adhesive.

Spacer 162 of masking structure 158 may be positioned between and/orcoupled to protective film 160 and rigid top component 164.Additionally, spacer 162 may couple rigid top component 164 toprotective film 160. In the non-limiting example, spacer 162 may beformed from any suitable double-sided adhesive that may couple rigid topcomponent 164 to protective film 160. As shown in FIG. 7B, spacer 162may only be coupled and/or formed between a portion of protective film160 and rigid top component 164. In the non-limiting example, spacer 162may be positioned between protective film 160 and rigid top component164 at a distance away from groove 128 and/or transition point 156, andmay not cover any portion of ink 150 a. As discussed herein, by notcovering any portion of ink 150 a, spacer 162 may allow ink 150 bapplied by sprayer 152 (see, FIG. 7C) to be sprayed and/or formed over aportion of ink 150 a.

Rigid top component 164 may be coupled to the double-sided adhesiveforming spacer 162 as discussed herein. As shown in FIG. 7B, rigid topcomponent 164 may extend to transition point 156, and/or may bepositioned directly adjacent groove 128 formed in cover 112.Additionally, rigid top component 164 may be positioned above, but maynot necessarily cover, ink 150 a formed on inner surface 124 of cover112. That is, and as discussed herein, rigid top component 164 may notdirectly cover ink 150 a because of the positioning of spacer 162 withinmasking structure 158. However, rigid top component 164 may bepositioned above ink 150 a, and may substantially prevent ink 150 a frombeing sprayed directly onto the surface by sprayer 152 during an inkspraying process. Rigid top component 164 may be formed from anysuitable rigid material that may hold its form during the sprayingprocess discussed herein. In non-limiting examples, rigid top component164 may be formed from a glass sheet, a fiberglass sheet or a reinforcedplastic sheet.

FIG. 7C shows a spraying process being performed on cover 112. In anon-limiting example, and as similarly discussed herein with respect toFIG. 6H, sprayer 152 may be utilized to apply ink 150 b to cover 112.Ink 150 b sprayed or applied by sprayer 152 may be diffused as it isapplied to cover 112. As a result of diffusing ink 150 b, and asdiscussed herein, ink 150 b may be applied directly to portions of cover112 (e.g., groove 128), when sprayer 152 is positioned directly abovethe portion of cover 112, and ink 150 b may be indirectly applied tosurrounding portions of cover 112 that are adjacent the portion of cover112 that is receiving the directly applied ink 150 b.

As shown in FIG. 7C, sprayer 152 may directly apply ink 150 b intogroove 128 of cover 112. Sprayer 152 may also directly apply ink 150 bto contact surface 166 of rounded perimeter portion 134 of cover 112,which may be subsequently coupled to and/or contact shelf portion 120 ofhousing 102, as similarly discussed herein with respect to FIGS. 2-4.Sprayer 152 may move in a direction (D) to spray, apply and/or covergroove 128 and contact surface 166 with ink 150 b. Sprayer 152 may makea single pass over groove 128 and contact surface 166, or may makemultiple passes over groove 128 and contact surface 166 when sprayingand/or forming a uniform layer of ink 150 b on cover 112.

As discussed herein, rigid top component 164 of masking structure 158may be positioned over ink 150 a and may substantially prevent sprayer152 from directly spraying ink 150 b onto ink 150 a. However, because ofsprayer's 152 ink-diffusive characteristics, a portion of ink 150 b maybe indirectly sprayed or deposited on a portion of ink 150 a, directlyadjacent transition point 156. In a non-limiting example shown in FIG.7D, as sprayer 152 moves toward ink 150 a and masking structure 158,respectively, ink 150 b may be directly applied to groove 128 andtransition point 156. Additionally, ink 150 b may be indirectly sprayedunder rigid top component 164, and may be applied to a small portion ofink 150 a positioned adjacent transition point 156. The amount of ink150 b that may be indirectly applied to ink 150 a may be minimal and/ormuch less when compared to the amount of ink 150 b applied directly togroove 128 and/or contact surface 166. As discussed herein, rigid topcomponent 164 may prevent ink 150 b from being directly applied to ink150 a as sprayer 152 moves in a direction (D) toward and/or over rigidtop component 164. That is, because rigid top component 164 of maskingstructure 158 is positioned over ink 150 a formed on inner surface 124,ink 150 b from sprayer 152 may not be directly sprayed or deposited onink 150 a when sprayer 152 is positioned directly above rigid topcomponent 164.

FIG. 7E shows cover 112 after ink 150 a is pad printed on inner surface124 and ink 150 b is sprayed on groove 128 and contact surface 166. Inthe non-limiting example shown in FIG. 7E, ink 150 a and ink 150 b maybe substantially continuous on cover 112. Additionally, ink 150 a and150 b may include substantially uniform thicknesses throughout, and eachthickness of ink 150 a and ink 150 b may be substantially equal to eachother. However, as shown in FIG. 7E, and discussed herein with respectto FIG. 7D, an overlapping portion 167 of ink 150 b adjacent transitionpoint 156 may be indirectly deposited over ink 150 a. Overlappingportion 167 of ink 150 b indirectly deposited on ink 150 a may beminimal and/or negligible and may not affect the appearance and/orfunction of ink 150 a and/or ink 150 b. Although shown as having aminimal and/or slight thickness increase where overlapping portion 167of ink 150 b is indirectly deposited on ink 150 a, ink 150 b depositedon ink 150 a may form a substantially smooth, gradual controlled and/orseamless transition between ink 150 a and ink 150 b of cover 112. Thatis, by allowing a minimal amount of ink 150 b to be indirectly depositedon ink 150 a, the transition between ink 150 a and ink 150 b may besubstantially smooth and/or seamless, without changing, and specificallyincreasing, the thickness of the deposited ink significantly and/or overan extended length of ink 150 a.

FIGS. 8A-8D show another non-limiting example for applying ink 150 togroove 128 and portions of cover 112 positioned adjacent to groove 128using a pad printing process and a spraying process. It is understoodthat similarly numbered components may function in a substantiallysimilar fashion. Redundant explanation of these components has beenomitted for clarity.

Distinct from the non-limiting example shown in FIGS. 7A-7E, contactsurface 166 may also undergo a pad printing process. In the non-limitingexample shown in FIG. 8A, ink 150 c may be applied to at least a portionof contact surface 166 of cover 112 using a pad printing processsimilarly discussed herein with respect to FIG. 7A and ink 150 a.However, distinct from ink 150 a, which may include a uniform thickness,ink 150 c pad printed on contact surface 166 of cover 112 may include asloped portion 168, which may have a gradually decreasing thickness.Sloped portion 168 may be formed in ink 150 c during the pad printingprocess. As shown in FIG. 8A, sloped portion 168 may be formed in only aportion of ink 150 c, however, it is understood that ink 150 c mayinclude sloped portion 168 formed over the entire length of ink 150 c.Additionally, distinct from ink 150 a, ink 150 c formed on contactsurface 166 may not end and/or be positioned directly adjacenttransition point 156 b (i.e., transition between planar portion of cover112 and groove 128) of contact surface 166. Rather, ink 150 c may bepositioned proximate and/or spaced a distance away from transition point156 b. As discussed herein, the gradually decreasing thickness of ink150 c and ink 150 c positioning with respect to transition point 156 bmay allow ink 150 b to form a seamless transition over ink 150 c oncontact surface 166 and into groove 128.

Turning to FIG. 8B, masking structure 158 may also be utilized toprevent spraying ink 150 b on portions of inner surface 124 of cover112. In the non-limiting example shown in FIG. 8B, a protective fixture170 may be secured to cover 112. Similar to rigid top component 164,protective fixture 170 may be positioned above, but may not directlycover ink 150 c, such that during a spraying process, ink 150 b sprayedin groove 128 may also be sprayed and/or applied to ink 150 c, asdiscussed herein. In the non-limiting example shown in FIG. 8B,protective fixture 170 may also extend over contact surface 166 only asfar as ink 150 c, and may be secured to the side of cover 112 to preventany ink 150 b from being undesirably sprayed on outer surface 126 duringthe spraying process discussed herein. Protective fixture 170 may beformed from a substantially similar material (e.g., glass, fiberglass,reinforced plastic and so on) or from a material having substantiallysimilar characteristics (e.g., rigid) as rigid top component 164 ofmasking structure 158.

FIG. 8C shows the ink spraying process performed on cover 112. Assimilarly discussed herein with respect to FIG. 7D and masking structure158, the gap or space between ink 150 c and protective fixture 170 mayallow sprayer 152 to indirectly spray and/or apply ink 150 b over atleast a portion of ink 150 c. In the non-limiting example, ink 150 b maybe indirectly sprayed, applied and/or cover sloped portion 168 of ink150 c as sprayer 152 moves in a direction (D) toward protective fixture170 and ink 150 c on contact surface 166 of cover 112. Additionally, thepositioning of protective fixture 170 over ink 150 c may prevent sprayer152 from directly applying ink 150 b to ink 150 c when sprayer 152 ispositioned directly above ink 150 c, and/or protective fixture 170.

Turning to FIG. 8D, the indirect spraying and/or applying of ink 150 bto ink 150 c having the gradually reducing thickness, may allow ink 150b, 150 c formed on contact surface 166 to have a substantially uniformthickness. In the non-limiting example, and as similarly discussedherein with respect to FIG. 7E, ink 150 a, ink 150 b and ink 150 c mayall have a similar and/or uniform thickness after the pad printing andspraying process is performed on cover 112. Additionally, as shown inFIG. 8D, by forming ink 150 c with sloped portion 168, and subsequentlyapplying overlapping portion 167 b of ink 150 b over sloped portion 168,a substantially smooth, gradual controlled and/or seamless transitionbetween ink 150 b and ink 150 c may be formed on contact surface 166 atoverlapping portion 167 b.

FIGS. 9A-9D show another non-limiting example for applying ink 150 togroove 128 and portions of cover 112 positioned adjacent to groove 128using a pad printing process and a spraying process. Similar to FIG. 8A,the non-limiting example in FIG. 9A may also pad print ink 150 c oncontact surface 166 of cover 112 prior to performing an ink sprayingprocess. However, distinct from FIG. 8A, ink 150 c pad printed ontocontact surface 166 may include a uniform thickness, similar to ink 150a formed on inner surface 124. Also similar to ink 150 a, ink 150 cformed on contact surface 166 may be formed directly adjacent groove128, and may end at transition point 156 b of contact surface 166, asshown in FIG. 9A.

As shown in FIG. 9B, masking structure 158 and protective fixture 170may be utilized during an ink spraying process to prevent ink 150 b frombeing sprayed on portions of cover 112 (e.g., portion of inner surface124, outer surface 126) which do not require ink 150. In thenon-limiting example shown in FIG. 9B, and distinct from FIG. 8B,protective fixture 170 may be positioned over and may directly cover atleast a portion of ink 150 c formed on contact surface 166. Protectivefixture 170 may directly contact and cover a portion of ink 150 c, suchthat the covered portion of ink 150 c may not be sprayed and/or coveredby ink 150 b during the ink spraying process (see, FIG. 9C).

Also shown in FIG. 9B, protective fixture 170 may not completely coverink 150 c formed on contact surface 166 because protective fixture 170may not extend all the way to transition point 156 b. Rather, protectivefixture 170 may be positioned proximate and/or spaced a distance awayfrom transition point 156 b. As a result, the portion of ink 150 cpositioned directly adjacent transition point 156 b may be exposedduring the ink spraying process and may be covered by ink 150 b, asdiscussed herein.

FIG. 9C shows the ink spraying process performed on cover 112. Duringthe ink spraying process, ink 150 b may substantially be indirectlysprayed, applied and/or cover the exposed portion of ink 150 c formed oncontact surface 166. In the non-limiting example, protective fixture 170positioned directly on ink 150 c may only prevent sprayer 152 fromdirectly or indirectly applying ink 150 b to the covered portions of ink150 c. However, because ink 150 c extends to transition point 156 b, andprotective fixture 170 does not, the exposed portion of ink 150 cpositioned adjacent groove 128 may be covered by ink 150 b.

In order to prevent substantial build-up of ink 150 b on ink 150 c, andultimately increase the thickness of ink 150 formed on cover 112, thespray process may be modified. In a non-limiting example, sprayer 152may have restricted movement in direction (D) toward contact surface166, such that sprayer 152 may never be positioned directly over contactsurface 166, and therefore may not directly spray ink 150 b on theexposed portion of ink 150 c. In another non-limiting example wheresprayer 152 makes multiple passes over groove 128 to apply ink 150 b,sprayer 152 may only pass over adjacent exposed portion of ink 150 cand/or transition point 156 b once to prevent over spraying ink 150 c.

Turning to FIG. 9D, the spraying and/or applying of ink 150 b to theexposed portion of ink 150 c, may allow ink 150 b, 150 c to form asubstantially smooth, gradual controlled and/or seamless transitionbetween ink 150 b and ink 150 c on contact surface 166. In thenon-limiting example, and as similarly discussed herein with respect toFIG. 7E, ink 150 a, ink 150 b, and ink 150 c may include substantiallyuniform thicknesses throughout, and each thickness of ink 150 a, ink 150b, and ink 150 c may be substantially equal to each other. However, andsimilar to indirectly applied ink 150 b covering ink 150 a at transitionpoint 156 a, the overlapping portion 167 b of ink 150 b deposited on theexposed portion of ink 150 c may be minimal and/or negligible and maynot affect the appearance and/or function of ink 150 b and/or ink 150 c.Although shown as having a minimal and/or slight thickness increasewhere overlapping portion 167 b of ink 150 b is deposited on ink 150 c,overlapping portion 167 b of ink 150 b deposited on ink 150 c may form asubstantially smooth, gradual controlled and/or seamless transitionbetween ink 150 b and ink 150 c of cover 112. That is, by allowing aminimal amount of ink 150 b to be deposited on the exposed portion ofink 150 c, the transition between ink 150 b and ink 150 c may besubstantially smooth and/or seamless, without changing, and specificallyincreasing, the thickness of the deposited ink significantly and/or overan extended length of ink 150 c.

Although depicted as different patterns and/or colors in FIGS. 7A-9D, itis understood that ink 150 a, 150 b, 150 c may be the same ink material,and may only be shown using different patterns and/or colors to indicatethe distinct processes for forming ink 150 a, 150 b, 150 c. In anotherlimiting embodiment, it may also be understood that ink 150 a, 150 b,150 c may represent different ink material for forming each of the inkportions on cover 112.

The dimensions (e.g., length, thickness, and so on) of each componentforming masking structure 158/protective fixture 170 and/or thepositioning of masking structure 158/protective fixture 170 with respectto transition point 156 a and transition point 156 b may be based on, atleast in part, the properties and/or characteristics of ink 150 and/orthe spraying process performed on cover 112. In non-limiting examples,the distance of gap formed between rigid top component 164 and ink 150a, and/or the distance between rigid top component 164 and transitionpoint 156 a may be based on, but is not limited to, the size of sprayer152, the output (i.e., volume) of ink 150 b dispensed by sprayer 152,the distance between sprayer 152 and cover 112, the number of passes forsprayer 152 to form ink 150 b in groove 128, characteristics and/orphysical characteristics of ink 150 (e.g., viscosity, color, chemicalcomposition, etc.) and so on.

FIG. 10 depicts an example process for applying decorative ink to acover for an electronic device. Specifically, FIG. 10 is a flowchartdepicting one example process 1000 for applying decorative ink to agroove and/or other portions of a cover for an electronic device. Insome cases, the process 1000 may be used to form one or more covers 112for electronic device 100, as discussed above with respect to FIGS.7A-9D.

In operation 1002, ink may be pad printed on at least a portion of aplanar surface of the cover. The portion of the planar surface that maybe pad printed may be positioned adjacent a groove formed in the cover.In operation 1004, a masking structure may be positioned on the cover.The masking structure may be positioned adjacent the groove formed inthe cover. The masking structure may include, a protective film coupledto the planar surface of the cover, a spacer coupled to a portion of theprotective film, and a rigid top component coupled to the spacer. Therigid top component may be positioned over the ink pad printed on atleast the portion of the planar surface of the cover, as discussed inoperation 1002. In operation 1006, ink may be directly applied to thegroove formed in the cover. In operation 1008, ink may be indirectlyapplied to at least a portion of the ink pad printed on at least theportion of the planar surface of the cover. The indirect applying of theink in operation 1008 may further comprise forming a seamless transitionline between the pad printed ink on the portion of the planar surfaceand the indirectly applied ink.

Although the processes discussed herein are for forming a cover 112 forelectronic device 100, it is understood that the processed may beperformed on any component of electronic device 100 including materialsubstantially similar to cover 112. In a non-limiting example, theprocesses discussed herein may be performed on housing 102, wherehousing 102 is formed from a sapphire material. Housing 102 may besubstantially opaque, but may still be processed and/or polished in asimilar manner as discussed herein with respect to cover 112. Likewise,the processes described herein may be used on features other thangrooves; any suitable recess, depression or like feature may be formed,polished, and/or inked as described herein.

As discussed herein and shown in FIG. 1, electronic device 100 isimplemented as a wearable electronic device, such as a watch. However,it is understood that electronic device 100 may be implemented as anyother suitable electronic device, such as, for example, a smart phone, alaptop or desktop computer, a tablet computing device, a gaming device,a display, a digital music player, a health monitoring device, otherforms of wearable computing devices (e.g., glasses, jewelry, and thelike) and so on. Electronic device 100 may be configured to perform anya variety of functions, including providing health-related informationor data such as, but not limited to, heart rate data, blood pressuredata, temperature data, oxygen level data, diet/nutrition information,medical reminders, health-related tips or information, or otherhealth-related data. The electronic device may optionally convey thehealth-related information to a separate electronic device such as atablet computing device, phone, personal digital assistant, computer,and so on. In addition, electronic device 100 may provide additionalinformation, such as, but not limited to, time, date, health, statusesof externally connected or communicating devices and/or softwareexecuting on such devices, messages, video, operating commands, and soforth (and may receive any of the foregoing from an external device), inaddition to communications.

Electronic device 100 may include a housing 102 at least partiallysurrounding a display 104 and one or more buttons 106 or input devices.The housing 102 may form an outer surface or partial outer surface andprotective case for the internal components of electronic device 100,and may at least partially surround the display 104. The housing 102 maybe formed of one or more components operably connected together, such asa front piece and a back piece. Alternatively, the housing 102 may beformed of a single piece operably connected to the display 104. Housing102 may formed from a number of distinct materials including, but notlimited to, corundum (commonly referred to as sapphire), metal, glass,ceramic and/or plastic. Additionally, housing 102 may include adecorative and/or coating layer that be disposed on the outer and/or orinner surface of housing 102. The decorative layer and/or coating layermay be disposed on the surface(s) of housing 102 to protect theenclosure and/or provide a decorative feature (e.g., exterior color) forelectronic device 100. Housing 102, similar to cover 112 discussedherein with respect to FIGS. 2-10, may also include a groove (e.g.,groove 128) formed therein that may be formed, shaped, polished, inkedand/or painted using similar processes discussed herein.

Housing 102 may also have recesses 108 formed on opposite ends toconnect a wearable band 110 to electronic device 100. Wearable band 110may be used to secure wearable electronic device 100 to a user, or anyother object capable of receiving electronic device 100. In anon-limiting example where electronic device 100 is a smart watch,wearable band 110 may secure the watch to a user's wrist. In othernon-limiting examples, electronic device 100 may be secured to anotherpart of a user's body.

Display 104 may be implemented with any suitable technology, including,but not limited to, a multi-touch sensing touchscreen that uses liquidcrystal display (LCD) technology, light emitting diode (LED) technology,organic light-emitting display (OLED) technology, organicelectroluminescence (OEL) technology, or another type of displaytechnology. Cover 112 may be positioned above the touchscreen of display104 to protect display 104, as discussed herein.

Button 106 may include any suitable input/output (I/O) device forelectronic device 100. Specifically, button 106 may include an actuationcomponent in electronic and/or mechanical communication with theinternal components of electronic device 100, to provide user inputand/or allow the user to interact with the various functions ofelectronic device 100. In an embodiment, button 106 may be configured asa single component surrounded by housing 102. Alternatively, button 106may include a number of components, including an actuation component, inmechanical and/or electrical communication with one another and/orinternal component of electronic device 100. Button 106 may likewiseinclude or be disposed near a sensor, such as a biometric sensor, touchsensor, or the like. Similar to housing 102 and/or cover 112, button 106may be formed from corundum or sapphire, and as such, may also include agroove (e.g., groove 128) or similar shape formed in at least a portionof button 106. The groove formed in button 106 may be formed, shaped,polished, inked and/or painted using similar processes discussed hereinwith respect to groove 128 of cover 112 shown in FIGS. 2-10.

The foregoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the describedembodiments. However, it will be apparent to one skilled in the art thatthe specific details are not required in order to practice the describedembodiments. Thus, the foregoing descriptions of the specificembodiments described herein are presented for purposes of illustrationand description. They are not targeted to be exhaustive or to limit theembodiments to the precise forms disclosed. It will be apparent to oneof ordinary skill in the art that many modifications and variations arepossible in view of the above teachings.

What is claimed is:
 1. A method for forming a polished sapphirecomponent, the method comprising: performing a first polishing processusing a polishing tool on at least one of: a planar surface the sapphirecomponent, or a groove formed in the sapphire component adjacent theplanar surface; and performing a second polishing process on the grooveof the sapphire component using blasting media.
 2. The method of claim1, wherein the blasting media is a diamond encrusted resin-basedmaterial.
 3. The method of claim 2, wherein the diamond encrustedresin-based is elastic and deforms on impact with the groove.
 4. Themethod of claim 1, further comprising shaping the sapphire componentprior to performing the first polishing process.
 5. The method of claim4, wherein shaping the sapphire component comprises: lapping a sapphirematerial; forming at least one rounded perimeter portion in the sapphirematerial; laser cutting the groove in the sapphire material; andmachining the laser cut groove formed in the sapphire material.
 6. Themethod of claim 5, further comprising applying a decorative ink into thegroove formed in the sapphire material.
 7. The method of claim 6,wherein applying the decorative ink comprises: performing a preliminarypad printing process at least on the groove formed in the sapphirematerial; covering a portion of the sapphire material positionedadjacent the groove with a protective mask; spraying the groove with thedecorative ink; and performing a subsequent pad printing process on thegroove including the decorative ink.
 8. The method of claim 1, furthercomprising at least one of: chemical mechanical polishing a portion ofthe sapphire component; and diamond mechanical polishing a portion ofthe sapphire component.
 9. The method of claim 1, further comprisingannealing the polished sapphire component.
 10. A method of forming acover for an electronic device, the method comprising: forming a grooveon an inner surface of a sapphire component; performing at least oneintermediate polishing process on the groove of the sapphire component;annealing the sapphire component; and performing a final polishingprocess on at least a portion of the annealed sapphire component. 11.The method of claim 10, wherein the performing of the final polishingprocess on at least the portion of the annealed sapphire componentcomprises polishing the inner surface of the annealed sapphire componentadjacent the groove.
 12. The method of claim 10, wherein performing thefinal polishing process on at least the portion of the annealed sapphirecomponent comprises: utilizing a compliant polishing pad to polish theinner surface of the annealed sapphire component including the groovesuch that at least a portion of the compliant polishing pad contoursinto the groove.
 13. The method of claim 10, wherein shaping thesapphire component further comprises: forming rounded perimeter portionson an outer surface of the sapphire component; wherein the roundedperimeter portions are positioned substantially adjacent the groove. 14.The method of claim 13, wherein performing the final polishing processon at least the portion of the annealed sapphire component comprises:polishing the outer surface of the annealed sapphire component adjacentthe rounded perimeter portions.
 15. The method of claim 13, whereinperforming the final polishing process on at least the portion of theannealed sapphire component comprises: utilizing a compliant polishingpad to polish the outer surface of at least one annealed sapphirecomponent.
 16. The method of claim 10, wherein performing the at leastone intermediate polishing process comprises: polishing the sapphirecomponent including the groove using a polishing brush; and polishingthe sapphire component including the groove using a blasting media. 17.The method of claim 16, wherein polishing the sapphire component usingthe blasting media comprises: applying a diamond encrusted resin-basedmaterial into the groove formed on the inner surface of the sapphirecomponent.
 18. An electronic device comprising: a housing; and a covercoupled to the housing, the cover comprising: an inner surface having atleast one of an intermediate polish, or a final polish; a groove formedon the inner surface; an outer surface positioned opposite the innersurface, the outer surface having at least one of the intermediatepolish, or the final polish; and a rounded perimeter portion formedbetween the inner surface and the outer surface, the rounded perimeterportion positioned adjacent the groove.
 19. The electronic device ofclaim 18, wherein the cover further comprises a decorative ink formedwithin the groove on the inner surface.
 20. The electronic device ofclaim 18, wherein the cover is formed from a sapphire material.
 21. Amethod for applying a decorative ink to a cover for an electronicdevice, the method comprising: pad printing a first ink on at least aportion of a planar surface of the cover, the portion of the planarsurface positioned adjacent a groove formed in the cover; positioning amasking structure on the cover adjacent the groove, the maskingstructure comprising: a protective film placed on the planar surface; aspacer coupled to a portion of the protective film; and a rigid topcomponent coupled to the spacer and positioned over the first ink;directly applying a second ink to the groove formed in the cover; andindirectly applying a third ink to at least a portion of the ink padprinted on at least the portion of the planar surface of the cover. 22.The method of claim 21, further comprising forming a seamless transitionline between the first ink and the third ink.
 23. The method of claim21, further comprising preventing the second ink from being applied overan entirety of the first ink by using the rigid top component of themasking structure to block at least a portion of the second inkapplication.
 24. The method of claim 21, wherein positioning the maskingstructure on the cover comprises: covering at least a portion of thefirst ink with the protective film; and forming a gap between the rigidtop component and the first ink.
 25. The method of claim 21, whereinpositioning the masking structure on the cover comprises aligning therigid top component with the first ink.
 26. The method of claim 21,further comprising pad printing ink on at least a portion of a contactsurface positioned opposite the planar surface of the cover, the contactsurface and the planar surface separated by the groove formed in thecover.
 27. The method of claim 21, wherein indirectly applying the thirdink comprises diffusing an ink spray over a portion of the groove and atleast a portion of the first ink.